#求值54,96,83。。。。

def f(x):

    for i in x:

        s = 3*i**4-9*i**2+i/2

        print(s)

f(54,96,83,64,234,158,364)





#成绩的等级

def f(n):

    if n >= 90 and n <= 100:

        return 'A'

    elif n >= 80:

        return 'B'

    elif n >= 60:

        return 'C'

    else:

        return 'D'





#奇数位

def sb(lis):

    lis1 = []

    le = len(lis)

    for i in range(0,le,2):

        lis1.append(lis[i])

    return list



print(sb(eval(input())))



#四个数字1234

n = 0

lis = ['1','2','3','4']

for i in range(123,433):

    i = str(i)

    if len(set(i)) == 3 and max(i) < '5' and min(i) > '0':

        n += 1

        print(i)

print('一哈有{}个'.format(n))





#三个整数x,y,z

x,y,z = map(int,input().split())

l = [x,y,z]

m = n =len(l)-1

for i in range(m):

    for j in range(n):

        if l[j] > l[j + 1]；

            l[j],l[i+1] = l[j+1],l[j]

    n -= 1

print(l)



#奇偶

def f(n):

    s = 0

    if n%2 == 0:

        for i in range(2,n+1,2):

            s = s+1/if

    else:

        for i in range(1,n+1,2):

            s = s+1/i

    return s

print(f(4))



#isalpha哈哈哈

def f(m):

    a = b = c = d = 0

    for i in m:

        if i.isalpha():

            a += 1

        elif i.isdigit():

            b += 1

        elif i.isspace():

            c += 1

        else:

            d += 1

    return a,b,c,d

print(f('Da s132 a2da'))